It grabs you by the collar in episode one and never really lets go: Ikki barely lands back in Japan before armed men are on him and Kogane comes in swinging the living weapon fused to her right hand. Sanzigen went full CG here, and it earns it, because the Buranki don't fight like puppets, they fight like heavy machines with weight and bad tempers. The best idea in the show is that Oubu isn't piloted by a chosen boy alone. It's crewed, limb by limb, heart included, so every brawl is also a group of stubborn people trying to move as one body. Reoko and Entei exist to remind you what that looks like when the wiring goes wrong. Watch it for the noise and the momentum, stay because a weapon that has its own mind will absolutely decide it doesn't like you.
Azuma Ikki returns to his hometown after a decade abroad only to be captured by mysterious soldiers. Kogane, his childhood friend, intercepts his captors with an impossible weapon: a sentient mechanical arm grafted to her body. Ikki learns the shocking truth about his own biology and the world's hidden secret: humanity shares the planet with intelligent, modular weapons called Bubuki, fragments of a colossal sleeping titan known as Oumai. Forced into an unlikely alliance with Kogane and other Bubuki users, Ikki becomes caught between those who want to awaken the titan and those desperate to keep it asleep. The group races across Japan uncovering the mystery of what Oumai represents and why shadow organizations will kill to control its resurrection. As Ikki trains to master his own Bubuki, he grapples with fragmented memories of his past and questions about his connection to the looming god-machine beneath their feet. This is mecha action filtered through the lens of personal mystery, where giant weapons are secondary to the characters wielding them and what they're willing to sacrifice for the truth.